diff options
Diffstat (limited to 'fs/jffs2/compr_rubin.c')
-rw-r--r-- | fs/jffs2/compr_rubin.c | 82 |
1 files changed, 77 insertions, 5 deletions
diff --git a/fs/jffs2/compr_rubin.c b/fs/jffs2/compr_rubin.c index e792e67..1f3a441 100644 --- a/fs/jffs2/compr_rubin.c +++ b/fs/jffs2/compr_rubin.c @@ -1,23 +1,95 @@ /* * JFFS2 -- Journalling Flash File System, Version 2. * - * Copyright (C) 2001, 2002 Red Hat, Inc. + * Copyright © 2001-2007 Red Hat, Inc. * * Created by Arjan van de Ven <arjanv@redhat.com> * * For licensing information, see the file 'LICENCE' in this directory. * - * $Id: compr_rubin.c,v 1.20 2004/06/23 16:34:40 havasi Exp $ - * */ #include <linux/string.h> #include <linux/types.h> #include <linux/jffs2.h> -#include "compr_rubin.h" -#include "histo_mips.h" +#include <linux/errno.h> #include "compr.h" + +#define RUBIN_REG_SIZE 16 +#define UPPER_BIT_RUBIN (((long) 1)<<(RUBIN_REG_SIZE-1)) +#define LOWER_BITS_RUBIN ((((long) 1)<<(RUBIN_REG_SIZE-1))-1) + + +struct rubin_state { + unsigned long p; + unsigned long q; + unsigned long rec_q; + long bit_number; + struct pushpull pp; + int bit_divider; + int bits[8]; +}; + +#define BIT_DIVIDER_MIPS 1043 +static int bits_mips[8] = { 277,249,290,267,229,341,212,241}; /* mips32 */ + +#include <linux/errno.h> + +struct pushpull { + unsigned char *buf; + unsigned int buflen; + unsigned int ofs; + unsigned int reserve; +}; + + +static inline void init_pushpull(struct pushpull *pp, char *buf, unsigned buflen, unsigned ofs, unsigned reserve) +{ + pp->buf = buf; + pp->buflen = buflen; + pp->ofs = ofs; + pp->reserve = reserve; +} + +static inline int pushbit(struct pushpull *pp, int bit, int use_reserved) +{ + if (pp->ofs >= pp->buflen - (use_reserved?0:pp->reserve)) { + return -ENOSPC; + } + + if (bit) { + pp->buf[pp->ofs >> 3] |= (1<<(7-(pp->ofs &7))); + } + else { + pp->buf[pp->ofs >> 3] &= ~(1<<(7-(pp->ofs &7))); + } + pp->ofs++; + + return 0; +} + +static inline int pushedbits(struct pushpull *pp) +{ + return pp->ofs; +} + +static inline int pullbit(struct pushpull *pp) +{ + int bit; + + bit = (pp->buf[pp->ofs >> 3] >> (7-(pp->ofs & 7))) & 1; + + pp->ofs++; + return bit; +} + +static inline int pulledbits(struct pushpull *pp) +{ + return pp->ofs; +} + + static void init_rubin(struct rubin_state *rs, int div, int *bits) { int c; |